Predictable DNS Transaction IDs Enable Cache Poisoning in Built-in Resolver (Erlang OTP)
At a glance
- Source
- NVD
- EPSS
- EPSS 0.27 % · percentile 19 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- EEF
- NVD status
- Modified
Description
Generation of Predictable Numbers or Identifiers vulnerability in Erlang/OTP kernel (inet_res, inet_db modules) allows DNS Cache Poisoning. The built-in DNS resolver (inet_res) uses a sequential, process-global 16-bit transaction ID for UDP queries and does not implement source port randomization. Response validation relies almost entirely on this ID, making DNS cache poisoning practical for an attacker who can observe one query or predict the next ID. This conflicts with RFC 5452 recommendations for mitigating forged DNS answers. inet_res is intended for use in trusted network environments and with trusted recursive resolvers. Earlier documentation did not clearly state this deployment assumption, which could lead users to deploy the resolver in environments where spoofed DNS responses are possible. This vulnerability is associated with program files lib/kernel/src/inet_db.erl and lib/kernel/src/inet_res.erl. This issue affects OTP from OTP 17.0 before OTPÂ 28.4.2, OTPÂ 27.3.4.10 and OTPÂ 26.2.5.19, corresponding to kernel from 3.0 before 10.6.2, 10.2.7.4 and 9.2.4.11.
Weaknesses (CWE)
- CWE-340 — Generation of Predictable Numbers or Identifiers
References
- https://github.com/erlang/otp/security/advisories/GHSA-v884-5jg5-whj8
- https://cna.erlef.org/cves/CVE-2026-28810.html
- https://osv.dev/vulnerability/EEF-CVE-2026-28810
- https://www.erlang.org/doc/system/versions.html#order-of-versions
- https://github.com/erlang/otp/commit/36f23c9d2cc54afe83671dd7343596d7972839a5
- https://github.com/erlang/otp/commit/dd15e8eb03548c5e55e9915f0e91389ec6bad9fd
- https://github.com/erlang/otp/commit/b057a9d995017b1be50d6dc02edd52382f3231b8
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 4.0 | MEDIUM 6.3 | CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N | EEF |
| CVSS 4.0 | MEDIUM 6.3 | CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X | NVD · 6b3ad84c-e1a6-4bf7-a703-f496b71e49db (Secondary) |
| CVSS 3.1 | LOW 3.7 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N | NVD · nvd@nist.gov (Primary) |
European references
- ENISA EUVD · EUVD-2026-19582
- GCVE · GCVE-0-2026-28810
Affected configurations (NVD CPE)
cpe:2.3:a:erlang:erlang\/otp:*:*:*:*:*:*:*:*≥ 17.0 < 26.2.5.19cpe:2.3:a:erlang:erlang\/otp:*:*:*:*:*:*:*:*≥ 27.0 < 27.3.4.10cpe:2.3:a:erlang:erlang\/otp:*:*:*:*:*:*:*:*≥ 28.0 < 28.4.2
Affected products
| Product | Versions |
|---|---|
| Erlang · OTP | affected 3.0 < * |
| Erlang · OTP | affected 17.0 < * ; affected 07b8f441ca711f9812fad9e9115bab3c3aa92f79 < * |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |